TAMPA — The loss of center fielder Jacoby Ellsbury to a compression fracture in his right foot almost certainly will not keep the Red Sox from winning the American League East.

The Sox start a series against the second-place Tampa Bay Rays Tuesday night with a 7½-game lead in the division and only 17 games to play. The Rays are playing for a wild-card spot at this point, something even they have acknowledged.

The much more significant question for the Red Sox is whether Ellsbury will be in the lineup Oct. 4 when the Red Sox start their American League Division Series.

Advertisement

Ellsbury’s fracture is in the navicular bone and came as the result of a foul ball that came down upon his foot Aug. 28. There are degrees to which that bone can be fractured and the Red Sox have described Ellsbury as having a “non-displaced” fracture. That means, in basic terms, that the bone remains aligned properly.

On Sunday, manager John Farrell said with little hesitation that Ellsbury should return before the end of the regular season Sept. 29.

“We feel like he’ll return this year,” Farrell said. “We feel like he’ll be back with us before this year is out. We’re hopeful in the regular season, yes.”

Farrell said the team did not have a more precise timetable beyond saying Ellsbury would have his foot immobilized for five days. After getting a second opinion in Colorado Sunday, Ellsbury returned to Boston and will not be with the team for the series against the Rays.

“Obviously it’s big. He’s a big part of this team,” lefthander Jon Lester said. “Hopefully he’s a quick healer and he’ll be back soon for us.”

Advertisement

Ellsbury played seven games after the initial injury and hit .313 with three stolen bases. But he aggravated the injury and perhaps further fractured the bone Thursday when he stole second base in the 10th inning and eventually scored the winning run against the Yankees.

After not playing Friday, he was sent back to Boston for an exam and was found to have a fracture.

In 2010, a fractured navicular bone suffered in June essentially ended Dustin Pedroia’s season. After an ill-considered two-game comeback in August, he submitted to surgery.

But in 2012, Cody Ross missed only a month with what the Red Sox then described as a “small non-displaced fracture” of the navicular bone.

Ellsbury’s fracture, according to team sources, is smaller than what Ross had. But it’s uncertain how long he will be out.

Advertisement

Complicating the issue is the contentious relationship Ellsbury has had with the Red Sox regarding his medical care. In 2010, Ellsbury accused the team’s medical staff of not properly diagnosing whether he had bruised or fractured ribs.

Last season, a partially dislocated shoulder led to Ellsbury missing three months — well beyond initial projections.

Ellsbury has disputed claims that he is prone to injury, pointing out correctly that the fractured ribs and dislocated shoulder were the result of collisions. A foul ball off his foot would fit into the same category of random bad luck.

On Saturday, Farrell said several times how upset Ellsbury was about not playing. On Sunday, following a 4-3 loss to the Yankees, teammates also came to his defense.

“Knowing Jacoby, he’s going to do what he can to try and play,” said catcher Jarrod Saltalamacchia. “I’m not a trainer or doctor, so I don’t know what they’ve told him or what his decision is, but I know that he wants to be out there.”

Not having Ellsbury in the postseason would change the look of the Red Sox offense. He leads the majors in stolen bases with 52 and is tied for 10th in runs with 89. Only six players have more than his eight triples.

Based on Wins Over Replacement, an advanced statistic that encompasses offense and defense, Ellsbury has been the most valuable player on the Red Sox.

One good sign: The Red Sox are 10-4 in the 14 games Ellsbury has missed so far this season and have averaged a whopping 6.92 runs in those games. That statistic is skewed given the relatively small number of games but still speaks to the potential of the offense, even without Ellsbury.

The Sox do not lack for options. Shane Victorino has hit leadoff 214 times in his career, six times this season. He also has been a center fielder for most of his career.

Rookie Jackie Bradley Jr. has started the last two games in center, going 2 for 6 with two walks and two runs. Bradley has hit .172 with a .596 OPS in 25 major league games this season.

Over 80 games for Triple A Pawtucket, Bradley hit .275 with an .842 OPS.

The Red Sox long have believed in Bradley’s promise and could look at Ellsbury’s absence as an opportunity to see what the former supplemental first-round draft pick can do — particularly with Ellsbury coming up on free agency.

“I feel like I’m ready, but that’s not for me to decide,” Bradley said. “I’ve learned a lot this season and I’m comfortable here and with this team.”

Bradley is considered one of the best defensive center fielders in the game and has a much stronger arm than Ellsbury.

In 2007, Ellsbury played only 33 games in the regular season before becoming a significant contributor in the postseason. He was 9 for 25 in 11 playoff games and scored eight runs.

If Ellsbury cannot return, Bradley could make a similar impact.

For now, Farrell has said the Red Sox will mix and match. If Victorino plays center field on a more regular basis, the Sox could ask more from Daniel Nava and Jonny Gomes.

Mike Carp, a productive player off the bench, also has outfield experience.

“We’ve got a lot of guys in this clubhouse that can pick him up,” said Saltalamacchia. “You don’t want to lose anybody like Jacoby, but we’ve just got to continue to fight and do what we do.”